Fatigue is a commonly reported symptom in patients with AIDS. The causes of fatigue are multifactorial and include the disease itself, antiviral therapies, anemia, depression and malnutrition. Our preliminary data suggest that micronutrient deficiencies, specifically carnitine deficiency, may be an important factor in fatigue. Carnitine plays a major role in energy metabolism. Systemic depletion is characterized by weight loss, fatigue, muscle weakness, decreased tolerance to metabolic stress and cardiomyopathy. WE found deficiency of the micronutrient carnitine in 6/10 patients with end stage AIDS presenting with canitine deficiency. Symptoms of fatigue and functional status improved significantly in those patients who received oral L-carnitine supplementation. Objectives: a) to determine the effect of L-carnitine therapy on symptoms of fatigue in patients with terminal AIDS and serum carnitine deficiency; and b) to determine the effect of L-carnitine therapy on performance status, cognitive function, mood, quality of life, and motor activity in these patients. Study Design: We propose to conduct a Phase II developmental randomized double-blind placebo-controlled study to determine the effect of the micronutrient L-carnitine on fatigue and other outcomes in patients with terminal AIDS. A sample of 44 patients with terminal AIDS, fatigue and serum carnitine deficiency will be recruited into the intervention study. At the first visit, the patients will receive a baseline assessment of fatigue, performance status, cognitive function, mood, quality of life, and motor activity. a) During weeks 1-4, patients will be randomized to receive L-carnitine, 3g/day, or placebo. b) During weeks 5-8, all patients will receive L-carnitine dose at 3 g/day for a period of 4 weeks. The primary endpoint will be change in fatigue at 4 weeks. Analysis will evaluate group differences in the primary endpoint and outcomes. An interim analysis will be done once 15 patients have been observed in each group at 4 weeks. Paired and unpaired data analyses between groups will be conducted with the assistance of the statistician.